Expert: autohelp - 9/26/2008

Question
QUESTION: I have a 96 Eldorado SC Touring and was getting an "low oil pressure stop engine" warning every once in a while, there was always plenty of oil and the pressure seems fine, so I had the sensor replaced and now the warning is on all the time an unsure mechanic (that replaced the sensor) told me it needed to be "calibrated", but was to busy to do it. My question is, is this true can the sensor be calibrated and if so how?

ANSWER: The switch cannot be calibrated. It is preset by the manufacturer and cannot be changed.

Your mechanic took your money and ran with it.

You need to have an automotive technician put an external oil pressure gage on the engine oil pressure passage and actually see what the oil pressure is.

It IS possible that the wrong type of engine oil was installed in the engine on your last oil change and or if you have had problems with the driveability with the engine whereas a fuel injector or injectors are or were leaking fuel into the engine it is possible that the engine oil is saturated with gasoline and has thinned out the engine oil thus causing the oil light to illuminate.

What I would do FIRST is change the engine oil and filter and see if the oil light goes OUT.

---------- FOLLOW-UP ----------

QUESTION: Thanks for your reply - It has fresh oil and filter (the right kind), I'm not burning any oil and the engine performance is exceptional (would the engine perform well with low oil pressure?). I have not had the oil pressure checked I assumed (perhaps incorrectly) that the good performance would eliminate low pressure as a concern?

Answer
You can have low idle speed oil pressure and still have excellent performance.

Are you POSITIVE that the idle speed is at the correct rpm's ?.

If you just barely increase the idle speed and the light goes out this would tend to be low oil pressure caused by excessive bearing clearances and or a weak fuel pump.